<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Abilities;

use LIT\MCP\Abilities\Cursor;
use LIT\MCP\Tests\Unit\TestCase;

final class CursorTest extends TestCase
{
    public function testRoundTrip(): void
    {
        self::assertSame(40, Cursor::decode(Cursor::encode(40)));
    }

    public function testMissingCursorStartsAtZero(): void
    {
        self::assertSame(0, Cursor::decode(null));
        self::assertSame(0, Cursor::decode(''));
    }

    public function testTamperedCursorIsRejected(): void
    {
        self::assertNull(Cursor::decode('not-a-cursor'));
        self::assertNull(Cursor::decode(base64_encode('o:-5')));
        self::assertNull(Cursor::decode(base64_encode('o:12;DROP')));
    }

    public function testLimitIsClamped(): void
    {
        self::assertSame(20, Cursor::limit(null));
        self::assertSame(1, Cursor::limit(0));
        self::assertSame(100, Cursor::limit(500));
        self::assertSame(7, Cursor::limit(7));
    }

    public function testPageDetectsMoreRows(): void
    {
        $page = Cursor::page([1, 2, 3], 2, 10);

        self::assertSame([1, 2], $page['items']);
        self::assertSame(12, Cursor::decode($page['next_cursor']));
        self::assertNull(Cursor::page([1, 2], 2, 0)['next_cursor']);
    }

    public function testInvalidCursorErrorIsAValidationError(): void
    {
        self::assertSame('lit_validation_failed', Cursor::invalid()->get_error_code());
    }

    public function testInputPropertiesDescribeLimitAndCursor(): void
    {
        $properties = Cursor::inputProperties();

        self::assertSame(100, $properties['limit']['maximum']);
        self::assertSame('string', $properties['cursor']['type']);
    }
}